The Example storage engine is meant to serve mainly as a code example of the stub of a storage engine for example purposes only (or so the code comment at the start of ha_example.cc reads). In reality however, it’s not very useful. It likely was back in 2004 when it could be used as a starting point for starting some simple new engines (my guess would be that more than a few of the simpler engines started from ha_example.cc).

The sad reality is the complexity of the non-obviousness of the bits o the storage engine API you actually care about are documented in ha_ndbcluster.cc, ha_myisam.cc and ha_innodb.cc. If you’re doing something that isn’t already done by one of those three engines: good luck.

Whenever I looked at ha_example.cc I always wished there was something

• Choosing the Best Sharding Policy - Doran Levari (ScaleBase, using a video link)
• Performance Monitoring with Statsd and Graphite - Art van Scheppingen (Spil Games)
• Basic MySQL performance tuning for sysadmins - Daniël van Eeden (Snow)

Insert performance with no indexes (best to worst)

Query OK, 15000000 rows affected (1 min 20.25 sec)

tl;dr:
Make sure you flash an LSI-9211 to IT firmware rev#14 to get it to work 
with Linux and SSD trim.  You may have to downgrade from newer firmware
to older firmware to get the card to work.

I wonder how much longer the ARCHIVE storage engine is going to ship with MySQL…. I think I’m the last person to actually fix a bug in it, and that was, well, a good number of years ago now. It was created to solve a simple problem: write once read hardly ever. Useful for logs and the like. A zlib stream of rows in a file.

You can actually easily beat ARCHIVE for INSERT speed with a non-indexed MyISAM table, and with things like TokuDB around you can probably get pretty close to compression while at the same time having these things known as “indexes”.

ARCHIVE for a long time held this niche though and was widely and quietly used (and likely still is). It has the great benefit of being fairly lightweight – it’s only about 2500 lines of code (1130 if

Heyo!

Now that we’ve gone through the Percona Live MySQL Conference and Expo review and had an amazing turnout to talk about it, it’s time to open up the discussion around things that DBAs want to talk about and need to be conscientious of. Join us on Wednesday at 12:00pm PDT (19:00 GMT) to take part in the discussion and share your knowledge and experience with the following topics:

• Filesystems and MySQL — Which do you use and why?
  • Do you handle I/O alignment? How do you do it?
  • Scheduler changes?
• Nagios checks! — Any new checks you’ve added recently?
• The worst settings in MySQL that you always change
• What are the most important variables to you, and what do you set them to?

Original images from Flickr user jenniferwilliams

One of our clients, for various historical reasons, runs both MySQL and PostgreSQL to support their website. Information for user login lives in one database, but their customer activity lives in the other. The eventual plan is to consolidate these databases, but thus far, other concerns have been more pressing. So when they needed a report combining user account information and customer activity, the involvement of two separate databases became a significant complicating factor.

In similar situations in the past, using earlier

This is one close to my heart. I’ve recently written on other storage engines: Where are they now: MySQL Storage Engines, The MERGE storage engine: not dead, just resting…. or forgotten and The MEMORY storage engine. Today, it’s the turn of MySQL Cluster.

Like InnoDB, MySQL Cluster started outside of MySQL. Those of you paying attention at home may notice a correlation between storage engines not written exclusively for MySQL and being at all successful.

NDB

These days I’ve answer some questions about replication lag, and I realized that most of people does not correctly understand how this process works internally on MySQL, and why does delays happen:

• MySQL replication: most important config parameters for performance on slave server?
• mysql replication delay very serious

See the bellow image, it represents asynchronous replication on MySQL, I highly recommend you to read my other post:

“How Does MySQL Replication Works?”

See the bellow image, it represents how asynchronous replication works on MySQL

Bearing in mind the number on the image, let’s see how the process works:

• Item 1 in the image represents the clients executing queries on master, note that the master is capable to handle multiple simultaneous connections (it can be configurable by max_connections variable). 
• Master process these queries, and save it to his binary log(item number 2 in the image), then it can later on be replied on the